• KSCE Journal of Civil and Environmental Engineering Research
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• v.4 no.1
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• pp.1-10
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• 1984

This dissertation presents an exact solution for the shearing and normal stresses of an orthotropic plane body loaded by a pairtial-uniform shear load. The solution satisfies the equilibrium and compatibility equations concurrently. An Airy stress function is introduced to solve the problem related to an orthotropic half-infinite plane under a partial-uniform shear load. All the equations for orthotropy must be degenerated into the expressions for isotropy when orthotropic constants are replaced by isotropic ones. The author has evaluated all the equations of orthotropy and succeeded in obtaining exactly identical expressions to the equations of isotropy which were derived independently by means of L'hospital's rule. The analytical results of, isotropy ate compared with the simple results of other investigator. Since a concentrated shear load is a particular case of partial-uniform shear load, all the equations of partial-uniform shear load case are degenerated into the expressions for concentrated load case of isotropy and orthotropy. The formal solution is expressed in terms of closed form. The numerical results for orthotropy are evaluated for two kinds and two different orientations of the grain of wood. The type of wood considered are three-layered plywood and laminated delta wood. The distribution of normal and shearing stresses are shown in figures. It is noted that the distribution of stresses of orthctropic materials dependson the type of materials and orientations of the grain.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.5 no.3
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• pp.95-105
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• 1985

This dissertation presents an exact solution for the normal and shearing stresses of an orthotropic plane body loaded by a moment load. The solution satisfies the conditions of equilibrium compatibility equations concurrently and is governing for the body being in the elasto-plastic state. An Airy stress function is introduced to solve the problem related to an orthotropic half-infinite plane under a moment load. All the equations for orthotropy must be degenerated into the expressions for isotropy when orthotropic constants are replaced by isotropic ones. The author has evaluated all the equations of orthotropy and succeeded in obtaining exactly identical expressions to the equations of isotropy which were derived independently by of L'hosptials rule. The analytical results of isotropy are compared with the simple results of other investigator. Since moment Load under the elastic state and plastic state only is a particular case of moment load under the elasto-plastic state. All the equations of elasto-plastic state case are degenerated into the expressions for the each case. The formal solution is expressed in terms of closed form. The orthotropic constants are evaluated for two kinds and two different orientations of the grain of wood and two kinds of structures. The numerical results for orthotropy are evaluated for one kind and two different orientations of three-layered ply wood. The distribution of normal and shearing stresses are shown in figures. It is noted that the distribution of stresses of orthotropic materials depends on the type of materials and orientations of the grain and stiffening.

• Journal of Radiation Protection and Research
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• v.40 no.4
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• pp.252-260
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• 2015

This paper describes the technical background for the Korean wildlife radiation dose assessment code, K-BIOTA, and the summary of its application. The K-BIOTA applies the graded approaches of 3 levels including the screening assessment (Level 1 & 2), and the detailed assessment based on the site specific data (Level 3). The screening level assessment is a preliminary step to determine whether the detailed assessment is needed, and calculates the dose rate for the grouped organisms, rather than an individual biota. In the Level 1 assessment, the risk quotient (RQ) is calculated by comparing the actual media concentration with the environmental media concentration limit (EMCL) derived from a bench-mark screening reference dose rate. If RQ for the Level 1 assessment is less than 1, it can be determined that the ecosystem would maintain its integrity, and the assessment is terminated. If the RQ is greater than 1, the Level 2 assessment, which calculates RQ using the average value of the concentration ratio (CR) and equilibrium distribution coefficient (Kd) for the grouped organisms, is carried out for the more realistic assessment. Thus, the Level 2 assessment is less conservative than the Level 1 assessment. If RQ for the Level 2 assessment is less than 1, it can be determined that the ecosystem would maintain its integrity, and the assessment is terminated. If the RQ is greater than 1, the Level 3 assessment is performed for the detailed assessment. In the Level 3 assessment, the radiation dose for the representative organism of a site is calculated by using the site specific data of occupancy factor, CR and Kd. In addition, the K-BIOTA allows the uncertainty analysis of the dose rate on CR, Kd and environmental medium concentration among input parameters optionally in the Level 3 assessment. The four probability density functions of normal, lognormal, uniform and exponential distribution can be applied.The applicability of the code was tested through the participation of IAEA EMRAS II (Environmental Modeling for Radiation Safety) for the comparison study of environmental models comparison, and as the result, it was proved that the K-BIOTA would be very useful to assess the radiation risk of the wildlife living in the various contaminated environment.

• The Korean Journal of Physiology
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• v.2 no.2
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• pp.21-31
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• 1968

The appearance rates of antipyrine and urea into cerebrospinal fluid from blood were studied in the rabbits which were in the state of hypotension and of high permeability in the capillary beds following injection of histamine. The alteration in the distribution of electrolytes among various compartments of the brain and the permeability characteristics in the blood-cerebrospinal fluid barrier were also observed. Adult male rabbits, weighing around 2 kg, were used. Twenty four rabbits were divided into 3 groups. Besides the control group, histamine treated rabbits were categorized into 2 groups. $H_1$ consisted of the rabbits showing moderate responses to histamine and ranging from 62 to 80 mmHg in their mean anterial blood pressure. The animals which belong to $H_2-group$ showed severe responses to histamine and the mean anterial blood pressures dropped to 30-50 mmHg. Animals were anesthetized with nembutal, 30mg/kg i.v. The mean arterial blood pressure was read by means of the mercury manometer connected to the femoral artery. The animals, treated with histamine, were kept in hypotensive state at least for 40 minutes before the administration of the test-substances. The test-substances, 300 mg of urea and 200 mg of antipyrine, were dissolved in 3 ml of distilled water and were injected into the ear vein of the rabbit. After 10 minutes elapsed arterial blood sample was taken from the femoral artery and cerebrospinal fluid from the cisterna magna. Brain tissues were also analysed with respect to electrolytes in order to observe the disturbances in the electrolytes balance as well as in the function of the central nervous system. The results obtained were as follow: 1. The ratio of antipyrine concentration in cerebrospinal fluid to that of arterial blood plasma, that was the distribution ratio, was close to unity, revealing a well established equilibrium between the compartments of blood and cerebrospinal fluid in 10 minutes. In other words, there was no diffusion barrier with regard to antipyrine. The ratios over unity which were frequently seen in the histamine treated animals were attributable to the early penetration of the substance into the cerebrospinal fluid. 2. The appearance rates of urea into the cerebrospinal fluid in the histamine treated rabbits were higher in comparison with those of in the control animals. The increasing tendency in the rates was particularly remarkable in the $H_2-group$, showing the enhanced penetration of urea across the boondary. 3. In the htisamine treated $H_2-group$ the concentration of potassium in the blood plasma and cerebrospinal fluid well exceeded the control values and showed 8.5 and 9.0 mEq/l in average, respectively. Simultaneous drops in the brain tissue water were noticed, suggesting the leakage of intracellular potassium. 4. There was a coincidence in the rising pattern of potassium in the blood plasma and in the cerebrospinal fluid of $H_2-group$ and at least partial removal of the blood-cerebrospinal fluid barrier with respect to potassium was suggested in these animals. 5. The concentration of sodium in the blood plasma or in the cerebrospinal fluid showed no significant changes following histamine injection. However, sodium in the brain tissue revealed slight elevation in the histamine treated groups. 6. The ratios of the concentrations of potassium to those of sodium, [K]/[Na] in the brain tissues, were 1.92 in the control 1.82 in the $H_1$ and 1.52 in the $H_2-group$, respectively. The marked drop in the $H_2-group$ might represent neural dysfunction in the extremely hypotensive rabbits.

• Journal of the Korean Society of Groundwater Environment
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• v.7 no.3
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• pp.103-115
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• 2000

The formation of brown-colored precipitates is one of the serious problems frequently encountered in the development and supply of groundwater in Korea, because by it the water exceeds the drinking water standard in terms of color. taste. turbidity and dissolved iron concentration and of often results in scaling problem within the water supplying system. In groundwaters from the Pajoo area, brown precipitates are typically formed in a few hours after pumping-out. In this paper we examine the process of the brown precipitates' formation using the equilibrium thermodynamic and kinetic approaches, in order to understand the origin and geochemical pathway of the generation of turbidity in groundwater. The results of this study are used to suggest not only the proper pumping technique to minimize the formation of precipitates but also the optimal design of water treatment methods to improve the water quality. The bed-rock groundwater in the Pajoo area belongs to the Ca-$HCO_3$type that was evolved through water/rock (gneiss) interaction. Based on SEM-EDS and XRD analyses, the precipitates are identified as an amorphous, Fe-bearing oxides or hydroxides. By the use of multi-step filtration with pore sizes of 6, 4, 1, 0.45 and 0.2 $\mu\textrm{m}$, the precipitates mostly fall in the colloidal size (1 to 0.45 $\mu\textrm{m}$) but are concentrated (about 81%) in the range of 1 to 6 $\mu\textrm{m}$in teams of mass (weight) distribution. Large amounts of dissolved iron were possibly originated from dissolution of clinochlore in cataclasite which contains high amounts of Fe (up to 3 wt.%). The calculation of saturation index (using a computer code PHREEQC), as well as the examination of pH-Eh stability relations, also indicate that the final precipitates are Fe-oxy-hydroxide that is formed by the change of water chemistry (mainly, oxidation) due to the exposure to oxygen during the pumping-out of Fe(II)-bearing, reduced groundwater. After pumping-out, the groundwater shows the progressive decreases of pH, DO and alkalinity with elapsed time. However, turbidity increases and then decreases with time. The decrease of dissolved Fe concentration as a function of elapsed time after pumping-out is expressed as a regression equation Fe(II)=10.l exp(-0.0009t). The oxidation reaction due to the influx of free oxygen during the pumping and storage of groundwater results in the formation of brown precipitates, which is dependent on time, $Po_2$and pH. In order to obtain drinkable water quality, therefore, the precipitates should be removed by filtering after the stepwise storage and aeration in tanks with sufficient volume for sufficient time. Particle size distribution data also suggest that step-wise filtration would be cost-effective. To minimize the scaling within wells, the continued (if possible) pumping within the optimum pumping rate is recommended because this technique will be most effective for minimizing the mixing between deep Fe(II)-rich water and shallow $O_2$-rich water. The simultaneous pumping of shallow $O_2$-rich water in different wells is also recommended.

• Journal of the Korean Society of Groundwater Environment
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• v.7 no.1
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• pp.32-46
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• 2000

Hydrogeochemical and isotope ($\delta$$^{18}$ O, $\delta$D, $^3$H, $\delta$$^{13}$ C, $\delta$$^{34}$ S, $^{87}$ Sr/$^{86}$ Sr) studies of various kinds of waters (thermal groundwater, deep groundwater, shallow groundwater, and surface water) from the Yusung area were carried out in order to elucidate their geochemical characteristics such as distribution and behaviour of major/minor elements, geochemical evolution, reservoir temperature, and water-rock interaction of the thermal groundwater. Thermal groundwater of the Yusung area is formed by heating at depth during deep circlulation of groundwater and is evolved into Na-HCO$_3$type water by hydrolysis of silicate minerals with calcite precipitation and mixing of shallow groundwater. High NO$_3$contents of many thermal and deep groundwater samples indicate that the thermal or deep groundwaters were mixed with contaminated shallow groundwater and/or surface water. $\delta$$^{18}$ O and $\delta$D are plotted around the global meteoric water line and there are no differences between the various types of water. Tritium contents of shallow groundwater, deep groundwater and thermal groundwater are quite different, but show that the thermal groundwater was mixed with surface water and/or shallow groundwater during uprising to surface after being heated at depths. $\delta$$^{13}$ C values of all water samples are very low (average -16.3$\textperthousand$%o). Such low $\delta$$^{13}$ C values indicate that the source of carbon is organic material and all waters from the Yusung area were affected by $CO_2$ gas originated from near surface environment. $\delta$$^{34}$ S values show mixing properties of thermal groundwater and shallow groundwater. Based on $^{87}$ Sr/$^{86}$ Sr values, Ca is thought to be originated from the dissolution of plagioclase. Reservoir temperature at depth is estimated to be 100~1$25^{\circ}C$ by calculation of equilibrium method of multiphase system. Therefore, the thermal groundwaters from the Yusung area were formed by heating at depths and evolved by water-rock interaction and mixing with shallow groundwater.

• Journal of Animal Science and Technology
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• v.54 no.5
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• pp.323-329
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• 2012

Genome-wide association study was performed on data from 266 Hanwoo steers derived from 66 sires using bovine 10K mapping chip in Hanwoo (Korean cattle). SNPs were excluded from the analysis if they failed in over 5% of the genotypes, had median GC scores below 0.6, had GC scores under 0.6 in less than 90% of the samples, deviated in heterozygosity more than 3 standard deviations from the other SNPs and were out of Hardy-Weinberg equilibrium for a cut-off p-value of $1^{-15}$. Unmapped and SNPs on sex chromosomes were also excluded. A total of 4,522 SNPs were included in the analysis. To test an association between SNP and QTL, a single marker regression analysis was implemented in this study. SNP was assumed to be in LD with QTL in close proximity and the effect evaluated was additive effect (QTL allele substitution effect). The number of significant SNP at a threshold of P<0.001 was 3, 5, 5 and 4 loci for live weight at 6, 12, 18 and 24 months, respectively. For live weight at different ages, significant SNP were spread out across chromosome but some of significant SNP (rs29012453 and rs29012456 on BTA24) had shown highly significant effects. As for the distribution of size of SNP effects, few loci for live weight at different age had moderate effects (6~11%) but most of significant loci had small effects (2 to 5% of additive genetic variance) against total additive genetic variance. In conclusion, live weight at different age might be affected by few loci with moderate effect and many loci with small effects across genome in Hanwoo.

• Journal of Korean Medical classics
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• v.11 no.1
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• pp.416-512
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• 1998

The following conclusions are obtained from the studies on the chapters concerning phisiology, pathology, daily conduct, materia medica, pulse, and urinalysis from , of the "Four Tantras". 1. The theoretical basis forming the Tibetan Medicine is the substance of phlegm, bile, and wind each of which is divided into five kinds. These phisiological substances can be transformed into pathological factors when certain environment is formed. 2. In embryology, the semen of the father and menstral blood of mother is considered the most important condition in conception, and the Five factors are regarded as important. There is a detailed explanation of development of the fetus while it stays in the womb of mother during 38weeks, such as the formation of the viscera, channels, sense organs, etc. 3. There is metaphor which compares the human body with the king's palace. With the development of human anatomy, there is the detailed anatomical picture of anterior and posterior aspects of human body. And also there is the measurement of physiological constitution and the three fluids. 4. In division of the channels, they concerned the now of the blood and distribution of the nerve fibers, and each channel is connected with one another. The division of the cannel is namely embryonic channel, channel of existence, channel of connection, and the course of life principle. 5. The seven bodily constituents and three factors of phlegm, bile, and wind are important in sustaining the life of human body as well as growth and maturization, and when their equilibrium is broken, the human body is degnerated, and finally death comes. 6. The signs of death is divided into distant sign, remote sign, certain sign. and uncertain sign, and is used as a clue in diagnosis of the disease. Especially there is a mention about the mechanism of the dreams, and different dreams according to the condition of the patient. 7. In pathology, there is the cause of the disease, the environmental factors which can induce disease, the path by which disease come into the human body, the characteristics of the disease, and the kinds of disease. 8. There is a mention about the conduct, and it is divided into the daily conduct, the mental attitude, and the side-effects which can occur when one puts up with the physiological actions of the body. 9. The daily diet is divided into food and beverage. The food is divided again into grain, meat, fat, boiled food, and spiced food, and the beverage into milk, water, and wine. 10. The pulsation should be taken in lift hand to diagnose heart, small intestine, stomach, spleen, kidney, reproductive organ, and in right hand jungs, large intestine, liver, gall bladder, kidney, and bladder. In the healthy person, the pulse moves 5times in one perspiration, and the type of pulse is constant while the pulse moves 100times. But unhealthy person's pulse is different from this. The urinalysis is the unique part of Tibetan Medicine, and is important in examination of the disease. One should decide which of the three factors are dominant by the obervation of the color, amount of the steam and how long it lasts, odour, foam, and the shape of the swirl in three different states when the urine is hot, warm, and cold. One can determine the life of the patient and which viscera is the cause of the disease by the pulse, and whether the nature of the disease is hot or cold by the urinalysis. 11. The materia medica contains gemstones, minerals, plateau medication, and meat products.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.31 no.6
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• pp.423-433
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• 2019

In order to predict the seabed topography change due to the construction of offshore wind power structures in the west-southern sea of Korea, field observations for tides, tidal currents, suspended sediment concentrations and seabed sediments were carried out at the same time. These data could be used for numerical simulation. In numerical experiments, the empirical constants for the suspended sediment flux were determined by the trial and error method. When a concentration distribution factor was 0.1 and a proportional constant was 0.05 in the suspended sediment equilibrium concentration formulae, the calculated suspended sediment concentrations were reasonably similar with the observed ones. Also, it was appropriate for the open boundary conditions of the suspended sediment when the south-east boundary corner was 11.0 times, the south-west was 0.5 times, the westnorth 1.0 times, the north-west was 1.0 times and the north-east was 1.0 times, respectively, using the time series of the observed suspended sediment concentrations. In this case, the depth change was smooth and not intermittent around the open boundaries. From these calibrations, the annual water depth change before and after construction of the offshore wind power structures was shown under 1 cm. The reason was that the used numerical model for the large scale grid could not reproduce a local scour phenomenon and they showed almost no significant velocity change over ± 2 cm/s because the jacket structures with small size diameter, about 1 m, were a water-permeable. Therefore, it was natural that there was a slight change on seabed topography in the study area.

• Radiation Oncology Journal
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• v.13 no.3
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• pp.277-283
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• 1995

Purpose : This study was performed to measure dose alteration at the air-tissue interface resulting from rebuild-up to the loss of charged particle equilibrium in the tissues around the air-tissue interfaces. Materials and Methods : The 6 and 10-MV photon beam in dual energy linear accelerator were used to measure the surface dose at the air-tissue interface The polystyrene phantom sized $25{\times}25{\times}5\;cm^3$ and a water phantom sized $29{\times}29{\times}48\;cm^3$ which incorporates a parallel-plate ionization chamber in the distal side of air gap were used in this study. The treatment field sizes were $5{\times}5\;cm^2,\;10{\times}10\;cm^2\;and\;20{\times}20\;cm^2$. Air cavity thickness was variable from 10 mm to 50 mm. The observed-expected ratio (OER) was defined as the ratio of dose measured at the distal junction that is air-tissue interface to the dose measured at the same point in a homogeneous phantom. Results : In this experiment, the result of OER was close or slightly over than 1.0 for the large field size but much less (about 0.565) than 1.0 for the small field size in both photon energy. The factors to affect the dose distribution at the air-tissue interface were the field size, the thickness of air cavity. and the photon energy. Conclusion : Thus, the radiation oncologist should take into account dose reduction at the air-tissue interface when planning the head and neck cancer especially pharynx and laryngeal lesions, because the dose can be less nearly $29{\%}$ than predicted value.